unmounted sd card

I recently got a Droid tablet.I used the same Gmail account for the Google playstore as I use for HTC XL Sensation. I was amused that the apps were automatically transfered from the phone to the tablet. I was expecting that the pics and music files would also be transferred to the tablet automatically, but it did not happen. I noticed when I tried to access gallery and music files, the internal sd card is unmounted. There was no external sd card for the tablet yet. What could have happened? How do I recover the internal sd card and all my photos and music FILES? Thanks